LinkedList TDE #WIP

# -*- coding: utf-8 -*-
"""
Created on Tue Sep 15 20:02:51 2015

@author: gregory.mendes
"""

class LinkedList:

        def __init__(self, value = None):
            self.value = value
            self.next = None

        def is_empty(self):
            if(self.head) == None:
                return True
            else:
                return False


        def __len__(self):
            if self.is_empty() == True:
                return 0
            else:
                if self.next != None:
                    return 1 + self.next.size()
                else:
                    return 1

        def head(self):
            return self.value


        def tail(self):
            if self.is_empty == True or self.next == None:
                return self.value
            else:
                return self.value + self.tail()

        def extend(self, L):
            if self.is_empty() == True:
                self.value = L.value
            # terminar aqui


        def append(self, value):
            if self.value is None:
                self.value = value
            elif self.next is None:
                self.next = LinkedList(value)
            else:
                self.next.append(value)


        def prepend(self, value):
            if self.value is None:
                self.value = value
            else:
                link = LinkedList(self.value)
                link.next = self.next
                self.value = value
                self.next = link


        def __eq__(self, other):
            if not type(other) is LinkedList:
                return False
            if other.is_empty():
                if self.is_empty():
                    return True;
                else:
                    return False
            if other.value == self.value and \
                other.next  == self.next:
                  return True
            else:
                  return False


        def __str__(self):
            return "[" + str(self.__str_values__()) + "]"

        def __str_values__(self):
            if self.is_empty():
                return ""
            elif self.next is None:
                return str(self.value)
            else:
                return str(self.value) + ", " + self.next.__str_values__()

        def __bool__(self):
            if(self.head) == None:
                return False
            else:
                return True